▎ 摘　　要

NOVELTY - Long-period fiber grating sensor based on graphene oxide/cellulose acetate functionalization comprises an input fiber, a long period fiber grating probe and an output fiber. One end of the long period grating probe is connected to the input fiber, and the other end is connected to the output fiber. The optical fiber probe is coated with a graphene oxide/cellulose acetate composite film, which forms intermolecular hydrogen bonds when the graphene oxide and cellulose acetate are physically blended. USE - The grating sensor is useful in sensing system for measuring concentration of ammonia gas (claimed). ADVANTAGE - The sensor has high measuring precision and sensitivity, high stability and non-destructive detection, and can be quickly desorbed and can be used for real-time detection. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for sensing system for measuring the concentration of ammonia gas, comprising light source, long-period fiber grating sensor, signal receiving and processing unit. The long-period fiber grating sensor is the graphene oxide/cellulose acetate functionalized long-period fiber grating ammonia gas sensor. The output fiber of the long-period fiber grating sensor is connected to the signal receiving and processing unit, and the long-period fiber grating sensor is placed in an ammonia gas environment. The signal receiving and processing unit includes a spectrometer and a computer connected in sequence. The light emitted from the light source enters the long-period fiber grating probe through the input fiber, and the graphene oxide/cellulose acetate composite film coated on the side of the grating adsorbs ammonia molecules. The sensing signal changes and is conducted through the output fiber into the signal receiving and processing unit. The signal receiving and processing unit collects the transmitted light information and calculates the ammonia gas concentration.